MySQL CURTIME And CURRENT_TIME Functions: Get The Current System Time

The CURTIME() and CURRENT_TIME() functions in MySQL are used to return the current time. Both functions do not require any arguments and they both return the current time in 'HH:MM:SS' format.

Prerequisites:

A MySQL server up and running.
Access to a MySQL user account with privileges to create, modify, and query tables.

Tutorial:

Connect to the MySQL server:

To start the mysql command-line client, open your terminal or command prompt, and enter:

mysql -u [username] -p

Replace [username] with your MySQL username and enter your password when prompted.

Using the CURTIME() function:

The basic syntax for using the CURTIME() function is as follows:

SELECT CURTIME();

This will return the current time.

Using the CURRENT_TIME() function:

Similarly, you can use the CURRENT_TIME() function to get the current time:

SELECT CURRENT_TIME();

This will also return the current time.

Both CURTIME() and CURRENT_TIME() functions will give you the same result.

Using CURTIME() and CURRENT_TIME() with a table:

Suppose you have a table named events with a column named event_time. You can use the CURTIME() or CURRENT_TIME() function to find all events happening at the current time like this:

SELECT *
FROM events
WHERE event_time = CURTIME();

SELECT *
FROM events
WHERE event_time = CURRENT_TIME();

Both these queries will return a list of events happening at the current time.

Exit the MySQL command-line client:

EXIT;

By using the CURTIME() or CURRENT_TIME() function in MySQL, you can easily get the current time. These functions can be useful for finding records associated with the current time, among other things.

How to Use CURTIME in MySQL:
- The CURTIME function is used to retrieve the current time.
```
SELECT CURTIME();
-- Output: Current time in 'HH:MM:SS' format
```
How to Use CURRENT_TIME in MySQL:
- CURRENT_TIME is an alternative to CURTIME for fetching the current time.
```
SELECT CURRENT_TIME();
```
Getting the Current Time in MySQL with CURTIME:
- Retrieve the current time using CURTIME.
```
SELECT CURTIME() AS current_time;
```
Getting the Current Time in MySQL with CURRENT_TIME:
- Achieve the same result using CURRENT_TIME.
```
SELECT CURRENT_TIME() AS current_time;
```
MySQL CURTIME vs CURRENT_TIME Comparison:
- Both functions provide the current time; choose the one that fits your preference.
```
SELECT CURTIME() AS curtime_example, CURRENT_TIME() AS current_time_example;
```

Using CURTIME in SELECT Queries in MySQL:

Incorporate CURTIME in your SELECT queries.

SELECT user_id, username, last_login_time
FROM users
WHERE last_login_time > CURTIME() - INTERVAL 1 HOUR;

Using CURRENT_TIME in WHERE Clause in MySQL:

Utilize CURRENT_TIME for time-based WHERE conditions.

SELECT appointment_id, appointment_time
FROM appointments
WHERE appointment_time <= CURRENT_TIME();

Formatting the Current Time in MySQL:
- Format the time output using DATE_FORMAT.
```
SELECT DATE_FORMAT(CURTIME(), '%h:%i %p') AS formatted_time;
```
MySQL CURTIME and Time Zone Considerations:
- Be aware of time zone settings affecting CURTIME.
```
SET time_zone = '+00:00';
SELECT CURTIME();
```
Performing Time Calculations with CURTIME in MySQL:
- Perform time calculations with CURTIME.
```
SELECT CURTIME() + INTERVAL 30 MINUTE AS future_time;
```

Using CURTIME in MySQL Time Comparisons:

Compare times using CURTIME.

SELECT user_id, username
FROM users
WHERE last_activity_time < CURTIME() - INTERVAL 1 HOUR;